Cirrate octopus swims through the ocean

Filmed in the Taney Seamounts, west of San Francisco, it's part of a branch of the octopus family that is very elusive—preferring deep, dark waters far from the coastline—very rare—they only make up about 15% of all octopus species—and very, very old. In fact, what is thought to be the oldest octopus fossil yet found is a cirrate, dating around 296 million years old.
Cirrate octopuses are also very weird. We don't know a whole lot about their anatomy and physiology, but we do know that they lack "typical" octopus features, like ink sacs and the ability to move around by jet propulsion. Instead, cirrates swim using those fins on the sides of their heads. As for the eponymous "cirra", those are little filaments, similar to the cilia that line your nose, which are paired up with every sucker on a Cirrate octopus' arm. Nobody knows exactly what they do, but they may be involved, somehow, in trapping and handling of food.